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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Evaluating carbon dioxide as a causative agent of otolith crystallization in recirculating aquaculture systems

Shank, Dale 22 December 2020 (has links)
No description available.
42

Vulnerability of longfin inshore squid (Loligo pealeii) to predation: The influence of relative prey size and behavior

Staudinger, Michelle Dana 01 January 2010 (has links)
Cephalopods provide forage to a wide range of predators in marine food-webs. Despite their ecological importance, a basic understanding of the mechanisms controlling predation risk and demand is lacking. This is true of one of the most common species of squid found in the northwest Atlantic, the longfin inshore squid (Loligo pealeii). In this dissertation, I address this shortcoming by investigating the role that size and behavior play in influencing squid’s vulnerability to predation. I used long-term food habits, population survey, and commercial landings data, to quantify size-based patterns of predation respective to 25 species of predators. Additionally, I estimated the amount of overlap between predatory consumption and the fishery catch for squid by size. I found that finfish and elasmobranchs generally consumed juvenile and sub-adult squid, while marine mammals primarily targeted adults. Consequently, marine mammals had the highest overlap with the fishing industry for squid size resources. Although large squid were not common in predator diets, predators did not appear to be gape-limited when feeding on squid. This suggested that other factors, including behavior, were important in shaping size-based patterns of predation. I used a laboratory-based approach to quantify attack and capture behaviors towards squid by two predators representing contrasting foraging tactics. Bluefish (Pomatomus saltatrix) and summer flounder ( Paralichthys dentatus) were chosen as cruising and ambush predators, respectively. Patterns in attack rates suggested that size-selection on squid was constrained by passive processes rather than active choice in both predators. Size-dependent profitability functions were calculated by combining capture success rates, handling times, and relative prey mass, and determined that bluefish was the more efficient predator of squid. Lastly, I evaluated the occurrence and effectiveness of anti-predator responses used by squid in the presence of bluefish and flounder. Squid behavior depended on the type of predator present, and the survival value of primary and secondary defense behaviors differed during interactions with each predator. The results of this project are intended to improve the quality of management of squid and their predators by providing a better understanding of predator-prey interactions in the northwest Atlantic.
43

ONTOGENETIC VARIATION IN THE NUTRIENT STOICHIOMETRY OF JUVENILE FISH

Downs, Kelsea Nicole 11 January 2018 (has links)
No description available.
44

Spatial and temporal variability in aquatic-terrestrial trophic linkages in a subtropical estuary

Zapata, Martha J., Zapata 24 May 2018 (has links)
No description available.
45

The effect of trade books on the environmental literacy of 11th and 12th graders in aquatic science.

Lewis, Ann S. 08 1900 (has links)
The purpose of this study was to compare the environmental literacy of 11th and 12th graders who participated in an eighteen-week environmental education program using trade books versus 11th- and 12th-graders who participated in an eighteen-week, traditional environmental education program without the use of trade books. This study was conducted using a quasi-experimental research technique. Four high school aquatic science classes at two suburban high schools were used in the research. One teacher at each high school taught one control class and one experimental class of aquatic science. In the experimental classes, four trade books were read to the classes during the eighteen-week semester. These four books were selected by the participating teachers before the semester began. The books used were A Home by the Sea, Sea Otter Rescue, There's a Hair in My Dirt, and The Missing Gator of Gumbo Limbo. The instrument used to measure environmental literacy was the Children's Environmental Attitude and Knowledge Scale. This test was given at the beginning of the semester and at the end of the semester. The scores at the end of the semester were analyzed by 2 X 2 mixed model ANOVA with the teacher as the random effect and the condition (trade books) as the fixed effect. The statistical analysis of this study showed that the students in the experimental classes did not score higher than the control classes on the Children's Environmental Attitude and Knowledge Scale or on a subset of "water" questions. Several limitations were placed on this research. These limitations included the following: (1) a small number of classes and a small number of teachers, (2) change from the original plan of using environmental science classes to aquatic science classes, (3) possible indifference of the students, and (4) restrictive teaching strategies of the teachers.
46

Sensing array for coherence analysis of modulated aquatic chemical plumes

Cantor, Ryan Segler. January 2009 (has links)
Thesis (M. S.)--Chemistry and Biochemistry, Georgia Institute of Technology, 2009. / Committee Chair: Janata, Jiri; Committee Member: Lyon, Andrew; Committee Member: Weissburg, Marc.
47

Using Local Knowledge to Inform Commercial Fisheries Science and Management in Poland and Alaska

Figus, Elizabeth Carroll 12 May 2018 (has links)
<p> Science and decision making in commercial fisheries management take place in the context of uncertainty. This research demonstrates ways that local knowledge held by fishermen can be used to mitigate that uncertainty. This dissertation documents local knowledge of fishermen in Poland and Alaska, and contributes to the development of methods for utilizing that local knowledge in commercial fisheries management. Specific case study examples were developed through exploratory interviews with fishermen in the two study regions. Interviews were conducted with Baltic cod (<i>Gadus morhua</i>) fishermen in Poland and Pacific halibut (<i>Hippoglossus stenolepis</i>) fishermen in Alaska. Qualitative and quantitative methods were used to analyze local knowledge about ecosystems, as well as preferences held by fishermen about regulations. Cultural consensus analysis was used to quantify agreement among fishermen in Poland about the abundance and condition of cod, and generalized additive modeling was used to show how fishermen and scientists attributed different causes to similar observed phenomena. Multiple factor analysis and logistic regression were used to demonstrate how fishing characteristics influence encounters with incidental catch in the commercial fishery for halibut in Southeast Alaska. Finally, an analytic hierarchy process model was used to shed light on preferences halibut fishermen have about data collection methods on their vessels. All findings show how the inclusion of fishermen&rsquo;s local knowledge in fisheries management need not be limited to informal conversations or public testimony at meetings in order to be meaningfully interpretable by managers.</p><p>
48

Conservation Strategies for Eastern Brook Trout (Salvelinus fontinalis; Salmonidae)| A Comparative Analysis of Management Plans, Stocking Habits, and Angler Attitudes

Brunson, Michael 19 July 2017 (has links)
<p> In an effort to highlight best practices in the management of wild eastern brook trout, an examination was performed of brook trout management plans and stocking habits for seven randomly selected states within the species native range. Additionally, surveys were distributed to these state&rsquo;s members of Trout Unlimited (TU) in an effort to understand angler motivations, awareness of and attitudes about their state&rsquo;s stocking practices and protection of wild brook trout fisheries. The states selected were within the eastern brook trout&rsquo;s native range and included West Virginia, Tennessee, Pennsylvania, Maine, Vermont, Maryland, and North Carolina. While each state differs in its efforts to either restore or protect existing wild brook trout populations, all seven states continue to stock hatchery-raised brook trout to maintain a viable sport fishery. However, regarding stocking dynamics, each state has unique policies regarding where the stocking occurs in relation to how these efforts potentially impacts wild populations. Survey results indicated that, while the majority of TU members expressed a strong understanding of their states stocking practices, they were still strongly interested in gaining additional information, indicating a need for more transparency regarding stocking habits and practices. Furthermore, survey results indicated that a large percentage of TU members still enjoy fishing for popular, nonnative, sport fish such as bass and brown trout. Additionally, support for policies protecting wild brook trout diminished as opportunities for catching larger fish diminished along with the removal of popular, nonnative sport fish. Overall, results indicated a need for fisheries managers to work more closely with cold-water conservation organizations, such as Trout Unlimited, and their members to assist in the crafting of policies that benefit both the sport fishing industry and wild brook trout populations.</p>
49

Impacts of Anthropogenic Noise on Aquatic Invertebrates in Wetland Habitats

Hopson, Adrienne M. 31 July 2019 (has links)
No description available.
50

The Influence of Diet on the Stoichiometry of Nutrient Uptake and Release in a Piscivorous Fish

Busch, Kaitlyn May 13 July 2022 (has links)
No description available.

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